The next phase for most facilities is the ASHRAE Level-2 
audit/assessment. The Level-2 audit starts with the findings from the Level-1 audit and examines the building energy systems in detail in order to define a number of potential energy-efficiency improvements. This will include the Building Envelope, Lighting, HVAC, Domestic Hot Water, Plug Loads, and Compressed Air and Process Uses. The next step is a detailed analysis of energy consumption in order to quantify base loads, seasonal variation, and efficient energy costs. From there, the study should include an assessment of lighting, air quality, temperature, ventilation, humidity, and other conditions that could affect energy performance and occupant comfort. An overall performance simulation is usually included in the process so that the team can estimate changes in energy usage resulting from potential optimization projects as well as compare individuals data in order to cost estimations to put into action the tasks. This could be a computer simulation design, spreadsheet models, or a number of other engineering tools. The process also consists of detailed discussions with the building Ownership, Management, and Occupants to discover potential problem areas and explain financial as well as non-financial goals of the program.
The Level-2 audit should result in a concise report and briefing with the Owner and Management Team in order to describe possible Energy Efficiency Measures (EEMs) such as no- and low-cost measures, modifications to system controls and building automation, operational changes, and potential capital upgrades. The findings should include general expenses and overall performance metrics in addition to a means for the Owner to evaluate the EEMs and decide the direction to go with implementation.
Many of the EEMs revealed throughout the ASHRAE Level-2 audit can be implemented rapidly with quick or instant financial payback for the Owner. Other EEMs will need more detailed analysis of benefits, cost and other goals which are important to the Owner; the audit should determine next steps to accomplish this analysis and decision making. For other EEMs that require complex interaction among building systems or potentially large financial investments, it may be necessary to dig deeper into the building operation as well as the human factors influencing overall performance. This is where the ASHRAE Level-3 audit is needed.